As electronic circuits shrink, and as devices become smaller and more portable, voltage levels used by the electronics have decreased. While the use of lower operating voltages is applied to many electronic components, memory devices typically require higher voltages for data storage, retention, and access than is currently used for other components. For example, DRAMs (dynamic random access memories) internally produce a Vpp supply using charge pumps. The Vpp supply is used in word line boosting, and is considered essential for fundamental DRAM data storage, retention, and access. However, the efficiency of charge pumps has traditionally been low, and has been steadily declining with process technology migration.
More modern memory implementations, such as DDR4 (dual data rate version 4) addresses decreasing charge pump inefficiency by setting a somewhat higher input voltage to the DRAM devices than the voltage of typical electronic devices. JEDEC (Joint Electronic Device Engineering Council) has standardized 2.5 V as a standard input voltage from an external source to the memory devices. With the 2.5 V input voltage to the memory devices, the charge pumps are not required to step up the voltage as high as if the voltage were down at around 1.0-1.5 V as with many electronic circuits. However, even with the input voltage standardized at 2.5 V, the charge pumps are inefficient, and thus the source of a significant amount of power use in a system that uses memory devices.
Descriptions of certain details and implementations follow, including a description of the figures, which may depict some or all of the embodiments described below, as well as discussing other potential embodiments or implementations of the inventive concepts presented herein.